JPH1099434A - Cartrige retainer assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cartridge retainer assembly that is impossible to loosely move and is especially useful for a medicine administrating pen. SOLUTION: An insulin cartridge retainer assembly 10 consisting of two parts for a medicine administrating pen 11 comprises a nearly tubular cartridge retainer body 12 for receiving, supporting, and accurately positioning the shoulder part 28 of the medicine cartridge. A forefront member 20 for insertedly fitting a needle is snappedly fitted without looseness to the cartridge retainer body 12 so as to receive the constricted part 30 of the cartridge, a rubber diaphragm 32, and a pressedly fitted metallic sleeve 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a part of a medicine dispensing pen for holding a medicine cartridge, and more particularly, to a non-movable cartridge holder.

[0002]

2. Description of the Related Art A medication delivery pen is a hypodermic syringe used to automatically inject a precisely measured dose of medication. Such pens are widely used, for example, for diabetics to administer insulin.

[0003] A typical prior art medication delivery pen has a cartridge containing an amount of liquid medication sufficient for several doses. The cartridge includes a generally tubular, elongated glass cartridge having a pierceable rubber septum, which extends across the open end of the cartridge and a metal sleeve (pressed against the end of the cartridge). ) Is securely held in place. The cartridge also includes a rubber stopper slidably and fluid-tightly engaged with the inner wall of the cartridge.

[0004] Such a medication delivery pen also has a small diameter tube sized to closely engage a constricted portion of the cartridge and a metal sleeve crimped on the constricted portion to support and position the entire cartridge. A unitary molded cartridge retainer having a constriction is provided. The outer region at the distal end of the tubular constriction is formed with a row of screws for threadably receiving the mounting cap of the needle assembly. The drug delivery pen further includes a drug delivery device for engaging a proximal end of the cartridge retainer, the drug delivery device having a plunger for engaging a rubber stopper of the cartridge. The medication delivery device includes a dose setting structure used to select a longitudinal distance in which the plunger moves, and dispensing means for driving the plunger by the selected distance.

The needle assembly for a drug delivery pen includes an elongated needle cannula having opposed proximal and distal ends and a lumen extending between the proximal and distal ends. While a plastic cork is glued at an intermediate location along the needle cannula, the cork is rigidly connected to the end wall of the cylindrical cap. The cylindrical wall of the cap surrounds the proximal end of the needle cannula, and the cylindrical wall has
The cartridge retainer has an array of female threads that engages with external threads provided in the constricted portion of the cartridge retainer.

The use of this medication delivery pen by urging the cap of the needle assembly above the constriction of the cartridge retainer enough that the proximal end of the needle cannula pierces the rubber septum of the cartridge. Can be. Next, the cap is rotated to threadably engage the constricted portion of the cartridge retainer. Next, the drug administration device is operated to select an appropriate dose. Next, the protective shield covering the distal end of the needle cannula is removed and the distal end of the needle cannula is protruded. The dispensing means of the prior art dispensing device is then operated to bias the cartridge stopper distally to dispense the medicament through the lumen of the needle cannula. The needle is then withdrawn and the needle assembly is removed from the cartridge retainer and safely disposed of. The rubber septum of this cartridge can re-occlude spontaneously and then be punctured again to administer the drug. This process can be repeated until all the medicine in the cartridge is used up.

[0007]

Because the cartridge can undergo a considerable range of dimensional changes and considerable eccentricity, the entire cartridge is closely engaged, supported and positioned. It is often difficult to accurately form a cartridge retainer to obtain. Such dimensional changes and eccentricity may be due to the method of manufacturing the glass cartridge or by crimping a metal sleeve that holds the rubber septum in place. A change in dimensions can result in a cartridge that does not fit into the cartridge retainer, or a cartridge that is loosely supported and moves within the cartridge retainer. If it is eccentric, there is a possibility that the cartridge outer cylinder will not be properly positioned in the main body of the cartridge retainer or will not be aligned with the retainer main body.
Also, such eccentricity may prevent the constriction of the cartridge from sliding within the precisely sized constriction of the cartridge retainer. As a result, considerable quality control must be exercised to ensure that only cartridges within precisely set dimensional tolerances are used, resulting in high product rejection rates. . In order to reduce the rejection rate of this product and allow more cartridges to be accepted, prior art pens have a greater degree of eccentricity between the neck and the body of the cartridge. And a cartridge retainer having a wider body for the purpose of coping with the problem. The result is a larger pen, despite the desire for smaller dimensions.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to a two-part cartridge retainer assembly that is particularly useful for a medication delivery pen. This cartridge retainer assembly is composed of two parts, a substantially tubular body made of plastic, surrounding the outer cylinder of the cartridge, and a tip of a metal needle attachment insert. The tubular body is in supportable engagement with the converging wall (the wall forming the shoulder of the cartridge). The insertion tool tip is non-movably attached to the main body so as to surround the constricted portion of the cartridge. The distal end of the needle mount insert has an edge extending from its proximal end. This edge is sized to engage closely with a metal sleeve (sleeve crimped onto the cartridge to hold the rubber septum in place). The needle mounting insert tip of the cartridge retainer assembly has an axial length that prevents contact of the rubber septum with the cap or cork stopper of the needle assembly.
The insert tip is also made of metal to provide the necessary strength to withstand greater impact forces during the injection process.

The tip of the needle mounting insert is held by four locking tabs on the cartridge retainer. These four locking tabs lock at predetermined positions in four locking cavities formed at the distal end of the insertion tool. This snap fit allows each part to be assembled at the same time,
In addition, if the tip of the insertion tool is operated to remove the cartridge from the cartridge retainer, the cartridge retainer is broken and can no longer be used. 100%
A major advantage over prior art devices made of plastic is the strength and flexibility of the cartridge retainer. The metal insert tip withstands greater impact forces and is operable in situations where the plastic tip "cracks due to stress" and renders that part unusable. Further, the snap-fit insert tip allows various modifications to be made as one assembly to the cartridge retainer without reworking or manufacturing several different molds of the cartridge retainer. . Different insert tips can be manufactured and snap-fit into the same cartridge retainer body.

[0010]

The above and other aspects of the invention,
Features and advantages will become apparent from the following detailed description, read in conjunction with the accompanying drawings.

A cartridge retainer assembly according to the present invention is indicated generally at 10 in FIG.
The cartridge retainer assembly 10 is intended to be a part of the drug delivery pen 11 and
Is a generally tubular elongate body 1 having opposed proximal and distal ends 14 and 16 and a cartridge receiving cavity 18 (shown in FIG. 2) extending between the proximal and distal ends.
Two. A generally tubular needle attachment insert tip 20 is snap-fitted within distal end 16 of body 12. Main body 12 of cartridge retainer assembly 10
And the insertion tool tip 20 are both described in more detail below.

The cartridge retainer assembly 10 is sized and configured to receive a cartridge assembly 22 therein. The cartridge assembly 22 includes a cartridge 23 having a substantially tubular outer cylinder. The outer cylinder has an open proximal end 26 and an inwardly converging shoulder 28.
And an end 25 defined by A small diameter constriction 30 projects distally from the shoulder 28 of the outer cylinder on the cartridge 23, and the small diameter constriction 30 has a large diameter extending circumferentially thereabout at the distal end of the constriction 30. A tubular bead portion 24 having a diameter is formed. A pierceable and resealable rubber septum 32 extends completely across the open end defined by the constriction 30. The rubber diaphragm 32 is held in place by a metal sleeve 34 (a sleeve crimped around the circumferential bead at the end of the constricted portion 30). The cartridge 23 is pre-filled with a drug such as insulin or heparin, and is held therein by a rubber stopper 36. The stopper 36 is slidably and fluid-tightly engaged with the tubular wall of the outer cylinder. As will be described below, when a distal force is applied to the stopper 36, the medicine is pushed out of the pen 11.

The medication dispensing pen 11 further includes a prior art dispensing device indicated generally by the reference numeral 38.
The dosing device 38 is generally cylindrical and has opposing proximal and distal ends 40 and 42, respectively. A screw 41 is formed at the distal end 42 of the dispensing device 38 to be threadably engageable with the proximal end 14 of the body 12 of the cartridge retainer assembly 10. A plunger rod 44 projects distally from the administration device 38 and is sized to engage the stopper 36 of the cartridge assembly 22. The dosing device 38 has a known mechanism therein for setting a selected dose of medicament to be administered by the pen 11. To move the stopper 36 a distance to inject a selected dose of medicament with the cartridge from the assembly 22, a dispensing mechanism (not shown) includes a plunger rod 44.
Is operable to drive a selected distance toward the distal end. One particular prior art dosing device 38
Although shown in FIG. 1, it should be understood that other dispensing devices can be used with the cartridge retainer assembly of the present invention.

The medication delivery pen 11 further includes a needle assembly 46 having a metal needle cannula 48 having opposed proximal and distal ends 50 and 5.
2 and a lumen (not shown) extending completely between the proximal and distal ends. A cork stopper 54 is firmly attached at an intermediate position along the needle cannula 48, and a cap 56 is firmly attached to the cork stopper 54. The cap 56 of the needle assembly 46
The needle assembly 46 has a row of internal threads (not shown) to removably attach the needle assembly 46 to the cartridge retainer assembly 10.

As mentioned above, prior art cartridge assemblies 22 are prone to dimensional changes and eccentricities over a considerable range. In particular, as a result of crimping and attaching the metal sleeve 34 to the constricted portion 30, there may be a difference in the dimension, that is, the axial length, of the adjacent cartridge from one cartridge. Furthermore, significant eccentricity can occur between the constriction 30 and the body. Cartridge retainer assembly 10 accommodates dimensional changes and eccentricities that occur in prior art cartridge assemblies 22. FIG. 2 is an exploded perspective view of the cartridge retainer assembly 10, and FIG. 3 is a cross-sectional view thereof, both of which show features of the present invention which solve the above-mentioned problems. More specifically, as shown in FIG. 2, the main body 12 of the cartridge retainer assembly 10 includes a plurality of inwardly projecting supports 6 defining an arc portion concentric with the main body 12.
5 These supports 65 are separated from each other by notches 62. Each of the other supports 65 has a locking tab 66 formed at a distal end thereof for engaging with the locking cavity 73 of the insertion tool tip 20.

The main body 1 disposed in the base direction of the support 65
The second part defines a cartridge receiving chamber 68 having a substantially constant diameter slightly larger than the diameter of the cartridge barrel. The proximal end 14 of the body 12 has a row of screws 13 that engage threads provided on a distal end 42 of the drug delivery device 38. However, it should be understood that other releasable engagement means may be provided between the medication delivery device 38 and the cartridge retainer assembly 10. For example, the drug delivery device 38 may be provided with external threads and the cartridge retainer assembly 10 may be provided with corresponding internal threads, or use a bayonet-type fitting that uses protrusions and slots.

The needle mounting insert distal end 20 of the cartridge retainer assembly 10 has opposed proximal and distal ends 72 and 74, as shown in FIG. The proximal end 72 includes a plurality of locking cavities 73 sized and arranged to receive each of the locking tabs 66 provided on the arcuate support 65 of the cartridge retainer body 12. And

The proximal end 72 of the needle mounting insert distal end 20 is
An edge 76 extends from the proximal end. The edge is sized to closely engage a metal sleeve 34 crimped on the cartridge 23 to hold the rubber septum 32 in place. The distal end 74 of the needle mount insert tip 20 includes a generally annular end wall 84 having an aperture 86 which is formed in the needle cannula 48.
And extends therethrough for access at a proximal end 50 of the base. Between the proximal end 72 and the distal end 74 is a row of outwardly disposed screws 88. Screw 88
Are sized and arranged to engage a screw provided on a prior art needle assembly 46.

The needle mounting insert tip 20 and the cartridge retainer body 12 are engaged with each other before the pen 11 is sold by pushing the distal end 74 of the insert tip 20 into the proximal end 14 of the body 12. Are combined. At first,
This assembly is performed by aligning a locking cavity 73 provided at the proximal end 72 of the inserter tip 20 with a locking tab 66 on a support 65 provided at the distal end 16 of the body 12. After moving the inserter tip 20 and the body 12 relatively sufficiently, each of the locking cavities 73 will have a respective locking tab 6.
6 and engages with its locking tab 66, the body 12
Locks the insert tip 20 securely and non-movably over the distal end 16 of the insert. As shown in FIG. 2, the needle mounting insert tip 20 is retained by four locking tabs 66 on the cartridge retainer body 12, which are locked on the insert tip 20. Four locking cavities 73
To a predetermined position in the inside. This snap fit allows the components to be assembled simultaneously, and if the inserter tip 20 is manipulated in an attempt to remove it from the cartridge retainer body 12, the cartridge retainer body 12 is broken and is no longer usable. A major advantage over prior art devices made of 100% plastic is the strength and flexibility of the cartridge retainer. The metal insert tip 20 can withstand higher impact forces, operate in situations where the plastic tip will "stress crack" and possibly render the part unusable. It is possible. Further, the snap-fitting insert tip allows various modifications to be made to the cartridge retainer 10 as one assembly without reworking or manufacturing several different cartridge retainer molds. It is possible to manufacture different insert tips 20 and snap-fit into the same cartridge retainer body 12.

Inserting the cartridge 22 into the cartridge retainer assembly 10 allows the drug delivery pen 11 to be inserted.
Is continued. More specifically, the constricted portion 30 of the cartridge 22 and the crimped metal sleeve 34 are inserted into the open proximal end 14 of the body 12 of the cartridge retainer assembly 10 from the proximal direction to the distal direction. This crimped metal sleeve 34 will eventually penetrate completely through the body 12 and advance the cartridge 22 further into the cartridge retainer assembly 10.
The crimped metal sleeve 34 must be placed within an edge 76 that extends from the proximal end 72 of the needle attachment insert tip 20. As mentioned above, it is known that there are substantial dimensional changes and eccentricities between the neck and the body of prior art cartridges. If such an eccentricity exists, the crimped metal sleeve 34 rests on the edge 76 of the inserter tip 20 until the dimensional mismatch or eccentricity of the cartridge 22 is accommodated.
The sleeve 34 is centered with respect to the body 12.

As the cartridge 22 is moved further distally into the cartridge retainer assembly 10, the shoulder 28 of the cartridge 22 seats against the edge 76 of the insert tip 20. Thus, the rim 76 defines a position in the cartridge retainer assembly 10 where the cartridge 22 is fully seated and serves to ensure engagement with the cartridge 22. In this fully seated position, the septum 32 of the cartridge 22 is proximally spaced from the distal wall 84 of the needle mount tip 20, as best seen in FIG.

Next, the drug delivery device 38 can be assembled to the proximal end 14 of the body of the cartridge retainer assembly 10 such that the plunger rod 44 of the drug delivery device 38 engages the stopper 26 of the cartridge 22.

Next, the drug dispensing pen 11 can be used by attaching the needle assembly 46 to the needle attachment insertion tip 20 of the cartridge retainer assembly 10. This installation is done by screwing the cap 56 (not shown)
This is accomplished by moving the needle assembly 46 proximally along the outer circumference of the needle mounting insert tip 20 until it engages an external thread 88 on the needle mounting insert tip 20. As described above, the screw 88 of the needle attachment insert tip 20 is spaced from the distal end of the needle attachment insert tip 20.
In this manner, when the cap 56 is first advanced axially along the outer circumference of the needle mount tip, the needle assembly 46 is threadedly engaged with the needle mount insert tip 20 in a rotatable manner. The proximal end 50 of the cannula 48 punctures the rubber septum 32 of the cartridge 22. For this reason, the rubber diaphragm 3
The bevel defining the proximal tip 50 advances axially through the septum 32 without rotation that could tear the 2. The screw of the cap 56 is the tip 2 of the needle mounting insert.
After engagement of the zero screw 88, the cap 56 and the needle mount tip 20 need to be rotated relative to each other to advance the needle assembly 46 further. It will be appreciated that the needle attachment insert tip 20 is extremely small and cannot be easily grasped by the user of the medication delivery pen 11 and is partially covered by the cap 56. However, by rotating the body 12 of the cartridge retainer assembly 10, this relative rotation can be achieved.
In particular, as described above, the locking cavity 7 of the needle insertion tool tip 20
3 engages with a locking tab 66 of the body 12. Therefore,
The rotation of the body 12 is transmitted to the needle attachment tip 20 to allow the needle assembly 46 to be fully rotationally engaged.

Use of the medication delivery pen 11 is accomplished in a conventional manner using a medication delivery device 38. As described above, when the drug administration device 10 is operated, the cartridge 2
The liquid medicament in 2 is extruded in the distal direction. This drug is pushed through the lumen of the needle cannula 48. Also, the pressure of the liquid directed in the distal direction is increased by the diaphragm 32.
To extend distally. However, as described above and shown in FIG. 3, the diaphragm 32 is proximally spaced from the cork stopper 54 of the needle assembly 46 and is not biased into contact with the cork stopper 54. In this way,
The dripping or spilling of the liquid medicine can be substantially prevented. This is because the shoulder 28 of the cartridge is
Engagement with the edge 76 of the cartridge 22 allows for the cartridge 22 to be supported and accurately positioned. Therefore, the constricted portion 30 and the crimped needle sleeve 3
There is no need for the needle mounting insert tip 20 to engage the 4 closely.

After using the medication delivery pen 11, the needle assembly 46 is removed from the needle mounting insert tip 20 and discarded. The user may be encouraged to apply an antimicrobial agent to the end of the medication delivery pen 11. Such antimicrobial agents can adversely affect some plunger materials that may be used in drug delivery pens. However,
The two-part construction of the cartridge retainer assembly 10 includes a metal needle mount insert tip 20 that is resistant to antimicrobial agents that a user may apply. The cartridge retainer body 12 is made of Lexan, a transparent plastic material manufactured by GE Plastics.
(Registered trademark), and processed into the form of a cartridge retainer by an injection molding method. Inserting tool tip 20
Is made of aluminum and is formed using a combination of stamping and machining.

In the above description, it should be understood that the above embodiments of the present invention are merely illustrative of the various features of a cartridge retainer assembly for a medication delivery pen. Other suitable modifications, variations, and combinations of these features may be employed or used in such embodiments and are within the scope of the invention.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a medication delivery pen with a cartridge retainer assembly according to the present invention.

FIG. 2 is an exploded perspective view of a cartridge retainer assembly according to the present invention.

FIG. 3 is a cross-sectional view of the cartridge retainer assembly.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Cartridge retainer assembly 11 Drug administration pen 12 Cartridge retainer main body 13 Screw 14 Base end of cartridge retainer main body 16 End of cartridge retainer main body 18 Cartridge receiving cavity 20 Needle mounting insert tip 22 Cartridge assembly 23 Cartridge 26 Cartridge base end 28 Cartridge shoulder 30 cartridge neck 32 rubber septum 34 metal sleeve 36 stopper 38 drug delivery device 40 proximal end of delivery device 41 screw 42 distal end of delivery device 44 plunger rod 46 needle assembly 48 needle cannula 50 needle cannula base End 52 Needle cannula end 54 Cork stopper 56 Cap 62 Notch 66 Locking tab 68 Cartridge receiving chamber 72 Insertion tool proximal end 73 Locking cavity 74 End 76 edge 86 hole 88 screws Nyugu

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Douglas Paddock, New Jersey, USA 07419, Hamburg, Meadow Pond Road 40

Claims (8)

[Claims] 1. A drug cartridge having an outer cylinder, a constricted portion defining a cross section smaller than the outer cylinder, and a converging shoulder extending between the outer cylinder and the constricted portion. A cartridge retainer assembly having opposing proximal and distal ends and a chamber extending between the proximal and distal ends, the chamber engaging therein the outer cylinder of the cartridge. A generally tubular body, configured and configured, defining a plurality of inwardly projecting supports defining an end of the chamber, and at least one locking tab formed on one of the supports. A tubular body having a proximal end and a distal end, a generally tubular needle mounting insert distal end, wherein play, rotation, and axial movement between the needle mounting insert distal end and the body are provided. Front on the body to prevent movement Having a locking cavity for receiving at least one locking tab includes a needle mounting insert tip, a cartridge retainer assembly. 2. The cartridge retainer assembly of claim 1, wherein said needle mount insert tip engages said constriction of said cartridge to center said cartridge within said body. A cartridge retainer assembly comprising: 3. The cartridge retainer assembly according to claim 1, wherein said body comprises eight of said supports, four of said supports having said locking tabs, and said needle mounting insert. A cartridge retainer assembly having a tip with four of said locking cavities engaging said four locking tabs. 4. The cartridge retainer assembly according to claim 1, wherein the tip of the needle mounting insert and the main body are made of different materials. 5. The cartridge retainer assembly according to claim 1, wherein said needle mounting insert tip includes a row of external threads that threadably and releasably engage with the needle assembly. The screw provided at the tip of the insertion tool,
A cartridge retainer assembly disposed proximal to the distal end of the needle mount insert distal end. 6. The cartridge retainer assembly according to claim 1, wherein said body is made of a transparent plastic material, and said tip of said needle mounting insert is made of a metal material. 7. The cartridge retainer assembly according to claim 1, wherein said body is made of a transparent plastic material, and said tip of said needle mounting insert is made of aluminum. 8. The cartridge retainer assembly according to claim 1, wherein the tip of the needle attachment inserter has the shoulder and the outer cylinder engaged in the main body of the cartridge retainer assembly. A cartridge retainer assembly, wherein the cartridge retainer assembly defines a length sufficient to extend distally beyond the constriction of the cartridge.